Method of making chloracetic anhydride



Patented May 1 -1929.

@UN TED. STATES;

P TENT OFEICE.

CHARLES J. s'rEosACK'En AND CLARENCE C. SCHWEGLER, or MIDLAND, M CHIGA AssIGNoRs TO THE DOW CHEMICAL ooivrrANg, E MIDLAND, MICHIGAN, A 603- PORATION OF MICHIGAN.

No Drawing.

This invention relates to the manufacture of derivatives of anhydride type from chloroXy-organic compounds, and more partlcularly the manufacture of chloracetic anhy-- 5 drides; and it is among the objects of themvention to provide a procedure which is efficient and reliable. Other objects and advantages will appear as the description proceeds, I

To the accomplishment of the foregoing and related ei1ds,-the invention, then, consists of the features hereinafter fully described, and particulariy pointed out in the claims, the

following description settingaforth in detail but a few of the Various wayscin which the principle of the invention may be applied.

In proceeding in accordance with our invention, a chlor-oxy-organic compound is heated with an organic acid in the presence zoof a metallic chloride.

tallic chlorides may be used with greater or less effectiveness, for instance aluminum chloride," ferrimchloride, zinc chloride, etc., ordinarily the aluminum chloride being much preferable. The particular chlor-oxy compound and organic acid used will depend of course upon the-product sought, whether of aliphatic or aromatic type. For making .chloracetic anhydrides for instance, a. chloracetyl compound and a'chloracetic acid are employed. It is preferablqto apply heat so as to bring up the temperature gradually through the reaction stage, and then finally by raising to distillation temperature the an- :5 dlydride product may be taken off. Reduced pressure or vacuum may be appliedand is advantageous in some conditions.

As an illustration of the process: Monochlora'cetic acid in the proportion of 0 one mol is heated up with chloracetyl chloride s in about a ten (10) per cent excess of molec ular proportion, and in the presence of about one (1) per-cent of aluminumrchloride. The temperature is raised gradually, and under reduced pressure with a reflux condenser.

Hydrochloric goes off and the anhydride I product may be finally distilled'off at its distillation temperature. The monochloracetic Various of the me- METHOD OF MAKING CHLORACETIC ANHYDRIDE.

L Application filedwMarch 15, 1927. Serial No. 175,631.

.acid product is solid at ordinary temperatures, having a melting point of 46 C. The reaction occurring may be indicated as:

01120100011 onioloooi omolco omol o h For the preparation of the -dichlor-anhydrides, correspondingly dichloracetic acid, and for the preparation of the tri-anhydrides trichloracetic acid, and in each casethe corresponding di or tri acetyl chlor compounds, are required. The metallic chloride or aluminum chloride being 0& catalytic character is required in correspon ingly small proportions, ordinarily one (1) per cent being sufficient, and in soine cases less may-be effective- I 1y employed. I Q

It will thus be seen that in accordance with the particular product in view, anhydridetype compounds may be readily prepared.

Other modes of applying the principle of the invention may be employed, change being made as regards ,the details disclosed, provided the steps stated in any of the following claims, or the equivalent of such, be employeol.

We therefore particularly point out and distinctly claim as our invention l. A process of the character described, which comprises heating art acid chloride with an organic carboxylic acid in the presence of a metallic chloride.

2. A process of the character described, which comprises heating an acid chloride with an organic carboxylicacidcin the presence of aluminum chloride.

3. A process of the characterdescribed, which comprises heating an acid chloride with a chlor-organic carboxylic acid in the presence of a metallicchloride.

4. A process of the character described, which comprises heating an acid chloride with a chlor-organic carbox, lic acid in the presence of aluminum chlori e.

5. A process of the character described; which comprises heating a chlor-acetyl chlo-e ride with a chlor-acetic acid in the presence 95 of a-metallic chloride.

6. A process of the character described, 8. A process of the character described,

which comprisesheating'a chlor-a-cetyl chlowhich comprises heating up mono-chlor 10 ride with a chlor-acetic acid in theipresence' acetic acid and a slight molecular excess of of aluminum chloride. chlor-a'cetylj chloride in the presence of about 5 7. A processof the character described, one (1%) per cent of aluminum chloride.

which comprises heating chlor-acetyl chloride Signed by US this 7th day of March, 1927. with mono-chlor acetic acid in the presence CHARLES J. STROSACKER;

of aluminum chloride I w ,7 CLARENCE, C. SCHWEGLER. I 

